Renal Point-of-Care Ultrasound Findings and Downstream Computed Tomography Use, Urologic Intervention, and Emergency Department Length of Stay in Renal Colic.

BACKGROUND

Renal colic is a common emergency department (ED) presentation, and imaging practices vary despite increasing use of renal point-of-care ultrasound (rPOCUS).

OBJECTIVES

To evaluate the association between rPOCUS findings and Computed tomography (CT) utilization, ED length of stay (LOS), and downstream urologic interventions in patients with suspected renal colic.

METHODS

We conducted a retrospective cohort study of adults undergoing rPOCUS for suspected renal colic from January 2020 through January 2022. Standardized chart abstraction with double review of a subset captured prespecified clinical and imaging variables. Comparative analyses and regression models assessed predictors of CT utilization, stone detection, urologic intervention timing, and ED LOS.

RESULTS

Among 188 patients, 89 (47%) had hydronephrosis on rPOCUS. CT was obtained in 108 (57%) and was notably more common in patients with hydronephrosis on rPOCUS (72% vs. 44%; adjusted OR: 2.63, 95% CI: 1.29-5.46). Hydronephrosis predicted ureteral stone presence on CT (74% vs. 30%; OR: 6.71) and urologic intervention within 24 hours (26% vs. 6%; OR: 5.40). Clinically significant alternative diagnoses were uncommon (1.6%) and occurred only in patients without hydronephrosis. Mean LOS did not differ by hydronephrosis status (269 vs. 273 minutes; p = 0.81), but LOS was longer when CT was performed (p < 0.01). In multivariable analysis, CT utilization and abdominal tenderness were associated with longer LOS, whereas hydronephrosis was not.

CONCLUSIONS

Hydronephrosis on rPOCUS was associated with stone disease and early urologic intervention but not shorter ED LOS. CT utilization was higher in patients with hydronephrosis and remained the primary factor associated with prolonged ED throughput. These findings reflect contemporary imaging patterns and suggest that the operational benefits of rPOCUS may be limited when CT is obtained irrespective of ultrasound findings.